Predict Optimised Treatment in Attention Deficit/Hyperactivity Disorder

Exclusion Criteria:

• Known contra-indication to the use of methylphenidate.
• Pregnancy and females of child bearing potential who are not using a form of contraception and are at risk of becoming pregnant during the study.
• Known medical condition, disease or neurological disorder which might, in the opinion of investigator/s, interfere with the assessments to be made in the study or put ADHD patients at increased risk when exposed to optimal doses of the drug treatment (including, but not limited to, anxiety, tension or agitation; glaucoma; motor tics; family history or diagnosis of Tourette's syndrome; treatment with monoamine oxidase inhibitors, and within 14 days following discontinuation of monoamine oxidase inhibitors; serious structural cardiac abnormalities, cardiomyopathy, serious heart rhythm abnormalities, or other serious problems that may place them at increased vulnerability to the sympathomimetic effects of a stimulant drug; hypertension, heart failure, recent myocardial infarction, ventricular arrhythmia; psychotic disorder, bipolar disorder, family history of suicide, bipolar disorder and depression; prior history of seizures or prior EEG abnormalities; allergy to any of the inactive ingredients in Ritalin).
• History of physical brain injury or blow to the head that resulted in loss of consciousness of greater than 5 minutes.
• Prior treatment with methylphenidate or any other stimulant medication in the past 7 days.
• Known past or present substance dependence, including alcohol, as determined by The Mini International Neuropsychiatric Interview for Children and Adolescents (MINI Kid).
• Participation in an investigational study within four months of the baseline visit (excluding follow-up studies in which the test drug/device has been registered in a major market) in which subjects have received an experimental drug/device that could affect the primary end points of this study.
• Subjects who, in the opinion of the investigator, have a severe impediment to vision, hearing and/or hand movement, which is likely to interfere with their ability to complete the testing batteries.
• Subjects who, in the opinion of the investigator, are unable and/or unlikely to comprehend and follow the study procedures and instructions.
• Presence of any other co-morbid primary DSM IV disorder (other than conduct disorder or oppositional defiant disorder).
• Known history of hypersensitivity and/or anaphylaxis to methylphenidate.